Document Type
Journal Article
Publication Title
ISME Journal
Publisher
Springer
School
Centre for Marine Ecosystem Research / School of Science
RAS ID
31489
Funders
Funding information available at: https://doi.org/10.1038/s41396-019-0506-9
Abstract
Microbial eukaryotes are key components of the ocean plankton. Yet, our understanding of their community composition and activity in different water layers of the ocean is limited, particularly for picoeukaryotes (0.2–3 µm cell size). Here, we examined the picoeukaryotic communities inhabiting different vertical zones of the tropical and subtropical global ocean: surface, deep chlorophyll maximum, mesopelagic (including the deep scattering layer and oxygen minimum zones), and bathypelagic. Communities were analysed by high-tthroughput sequencing of the 18S rRNA gene (V4 region) as represented by DNA (community structure) and RNA (metabolism), followed by delineation of Operational Taxonomic Units (OTUs) at 99% similarity. We found a stratification of the picoeukaryotic communities along the water column, with assemblages corresponding to the sunlit and dark ocean. Specific taxonomic groups either increased (e.g., Chrysophyceae or Bicosoecida) or decreased (e.g., Dinoflagellata or MAST-3) in abundance with depth. We used the rRNA:rDNA ratio of each OTU as a proxy of metabolic activity. The highest relative activity was found in the mesopelagic layer for most taxonomic groups, and the lowest in the bathypelagic. Altogether, we characterize the change in community structure and metabolic activity of picoeukaryotes with depth in the global ocean, suggesting a hotspot of activity in the mesopelagic.
DOI
10.1038/s41396-019-0506-9
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Comments
Giner, C. R., Pernice, M. C., Balagué, V., Duarte, C. M., Gasol, J. M., Logares, R., & Massana, R. (2020). Marked changes in diversity and relative activity of picoeukaryotes with depth in the world ocean. The ISME Journal, 14(2), 437-449. https://doi.org/10.1038/s41396-019-0506-9